Refactor releases

[tvories]

I think it would be good to look at refactoring the release workflow. Things I'd like to see:

1. The ability to approve and merge multiple PRs in a single release. Currently, the chart releases on any PR merge. It would be good to approve a few minor PRs and squeeze them into a single release rather than releasing 5 times in a day.
2. Add the ability to include release notes in the PR or in the release process to notify what is changing in the release. The K8s-at-Home charts have some good examples of this.
3. Look at a better way to handle the chart version bump requirement to allow for contributions to be handled a bit better

Any other thoughts or suggestions?